Noise reduction level of Bluetooth headset

Noise reduction grade of Bluetooth headset: 1 passive noise reduction, which refers to in-ear earplugs, because earplugs are inserted into human ear canal through silicone sleeve. Therefore, it has a good effect of isolating external sound. Moreover, this noise reduction is full-frequency, that is, it is effective for sounds from 20 Hz to 20 Hz, and this passive noise reduction will not damage the sound quality. So the general HiFi earplugs are in-ear, which is the reason. Call noise reduction, call noise reduction, refers to the use of Bluetooth headset in the call, so that the other party can hear clearly. Common CVC noise reduction, such as Qualcomm. Its principle is to use the chip inside the Bluetooth headset to filter the signal received by the microphone, thus reducing the external wind noise. At the same time, you can also reduce the echo of the call tone from the other party.